20121320 has 32 divisors (see below), whose sum is σ = 47243520. Its totient is φ = 7698240.

The previous prime is 20121307. The next prime is 20121337. The reversal of 20121320 is 2312102.

It is a happy number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10016 + ... + 11855.

It is an arithmetic number, because the mean of its divisors is an integer number (1476360).

Almost surely, 2^20121320 is an apocalyptic number.

20121320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20121320 is an abundant number, since it is smaller than the sum of its proper divisors (27122200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20121320 is a wasteful number, since it uses less digits than its factorization.

20121320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21905 (or 21901 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 20121320 is about 4485.6794357154. The cubic root of 20121320 is about 271.9895108412.

Adding to 20121320 its reverse (2312102), we get a palindrome (22433422).

The spelling of 20121320 in words is "twenty million, one hundred twenty-one thousand, three hundred twenty".